During oil and gas production, wirelines are often lowered through some type of gate valve. Ideally, the wireline is removed from the well before the gate valve is closed. However, in some situations wireline removal prior to valve closure is not possible and the gate valve is closed on the wireline. Gate valves having wireline therethrough should be capable of shearing the wireline while closing and maintain a seal after the valve is seated. Accordingly, the gate valve sealing surfaces should be durable and able to withstand repeated cycling; this is especially true for gate valves used in the oil and gas industry. Since the valves are opened and closed often and usually under severe operating conditions, the durability of the sealing surfaces is important to avoid leakage and the necessity of having to frequently perform maintenance on the valves.
Typical wireline shearing gate valves require a hard brittle inlay, such as Stellite®, on the valve seating surface. The inlay provides a substrate with a high strength cutting edge. Valve materials are generally coated to improve valve durability. However, care must be taken when applying the hard inlay to avoid damaging the valve material coating. Inlay materials are generally not as durable as gate valve materials and can be easily scratched or damaged, thereby reducing sealing capacity.